Page:Popular Science Monthly Volume 43.djvu/445

Rh  together, and rejoin the line, to let another pair take their turn of activity, but presently, and again and again at intervals, to repeat their own performance. It has been said that the most active players of this extraordinary game are the men and boys. But occasionally the women take a part also. And it is noteworthy that when this is the case a wooden figure of a bird, a heron, is substituted for each of the whips, and a gentle peck with this bird is substituted for the far more serious lash of the whip. "I do not know," says Mr. Im Thurn, "that any equivalent example of the fact that the germ of the idea of courtesy to the weaker sex exists among people even in this stage of civilization is on record."

Cleansing Function of the Hair.—Dr. Henry Sewell calls attention, in Science, to an example of the subservience of form to function afforded by the arrangement of the epidermic scales constituting the outermost layer of animal hairs. The buried edges of the scales point toward the root of the hair, while the free edges project obliquely toward the tip; and a hair glides between the thumb and finger far more easily when pulled from root to tip than when pulled in the opposite direction. When rolled between the fingers it will gradually move parallel to its length in the direction of the root. It follows that foreign particles may be easily moved outward toward the tip of the hair and away from the body, while it would be hard to push them in the opposite direction. Every movement of the hair, especially frictional disturbance, must set up a current of foreign particles toward the hair tip. The value of this property as a cleansing factor is evident.

Telephotography.—Telephotography is the name of an art the purpose of which is the production of photographs of objects at considerable distances from the operator, of such quality and scale that they can be examined and interpreted in a manner that would be impossible to the naked eye. The term is parallel in meaning with telescopy, and the art has as its aim the recording on a photographic plate of a combination of a number of distinct and separate telescopic impressions that can be obtained by sweeping a telescope over a greater field than that included in its own field of view, in the same manner, but to a less degree, that ordinary photographs record a number of distinct and separate visual images or impressions obtained by passing the eyes rapidly and almost unconsciously through the "wide" and "deep" fields of view, as they are termed. The apparatus consists of a combination of the telescope and photographic apparatus, with special supplementary lenses for magnifying the image and obtaining a flat field, the descriptions of which, by Thomas R. Dallmeyer, the inventor, are too technical for available use here. By it magnified and clearly depicted views are obtained of objects that are situated at such distances from the photographer that ordinary photographic means have hitherto rendered so small and insignificant as to be useless—views that are superior beyond comparison to enlargements of ordinary negatives.



jugglers have exhibited a trick which consists in throwing knives at a person extended against a structure of boards, into which the knives appear to stick alarmingly close to the subject. The trick has been copied or imitated by European prestidigitateurs; but instead of real knife throwing and sticking, an illusion is arranged. Knives are hidden in recesses in the board structure, skillfully concealed by shutters, which open by a spring controlled by the target-subject. When a knife is thrown he moves one of these springs, and causes the hidden knife to emerge and appear as if stuck in the board, while the shutters instantly close; or the same is effected by means of wires controlled by persons behind the scene. The operator who throws the knife either casts it skillfully behind himself, among the scene-slides, or else throws it so that it shall strike, not into the boards, but on one side, where it falls noiselessly upon the carpet. The latter method is the best, because it enables the spectator to see the knife pass across the stage.

account of the Polynesian canoe is in preparation by Dr. N. B. Emerson, of Honolulu. The author points out in an article on the subject that the various migrations of the ancient Polynesians and their progenitors, from whatever sources derived, must have been accomplished in canoes or other craft, and that the waa, the pahi, etc., of to-day, however modified they may be under the operation of modern arts and appliances,